Pharmacoepidemiology and thalidomide embryopathy surveillance in Brazil

A New Strategy for the Old Challenge of Thalidomide: Systems Biology Prioritization of Potential Immunomodulatory Drug (IMiD)-Targeted Transcription Factors

Several molecular mechanisms of thalidomide embryopathy (TE) have been investigated, from anti-angiogenesis to oxidative stress to cereblon binding. Recently, it was discovered that thalidomide and its analogs, named immunomodulatory drugs (IMiDs), induced the degradation of C2H2 transcription factors (TFs). This mechanism might impact the strict transcriptional regulation of the developing embryo. Hence, this study aims to evaluate the TFs altered by IMiDs, prioritizing the ones associated with embryogenesis through transcriptome and systems biology-allied analyses. This study comprises only the experimental data accessed through bioinformatics databases. First, proteins and genes reported in the literature as altered/affected by the IMiDs were annotated. A protein systems biology network was evaluated. TFs beta-catenin (CTNNB1) and SP1 play more central roles: beta-catenin is an essential protein in the network, while SP1 is a putative C2H2 candidate for IMiD-induced degradation. Separately, the differential expressions of the annotated genes were analyzed through 23 publicly available transcriptomes, presenting 8624 differentially expressed genes (2947 in two or more datasets). Seventeen C2H2 TFs were identified as related to embryonic development but not studied for IMiD exposure; these TFs are potential IMiDs degradation neosubstrates. This is the first study to suggest an integration of IMiD molecular mechanisms through C2H2 TF degradation.

Thalidomide control and use: are these appropriate to extend the use and mitigate the risk of teratogenicity in Brazil?

Drug utilization research to describe the control of thalidomide in Brazil and its use in Minas Gerais state. An online questionnaire was sent to the Brazilian federative units to collect data concerning distribution, dispensation, user registration, and thalidomide adverse events. Distribution (2011-2018) and dispensing (2015-2018) data in Minas Gerais were obtained through the pharmaceutical care management system. Analysis of variance and Tukey test were used for data comparisons. Of the 16 participating federative units, 100% and 50% used electronic distribution and dispensing systems, respectively, and about 43% registered users. Adverse event reporting systems were scarce. A 44% reduction was observed in the distribution in Minas Gerais for the period. Dispensing remained constant (mean 0.0004 DDD/1,000 inhabitants/day) and occurred mainly for erythema nodosum leprosum and multiple myeloma. Off-label use (2.2%) was increasing. Most users were male (mean age 56 years) and thirty percent of women were of childbearing age. Thalidomide surveillance is a public health challenge. Despite the increased use and mandatory control, there is no national standardization, and adverse event reporting is incipient.

Implementation of a Pregnancy Prevention Programme (PPP) with a Controlled Distribution System (CDS) for the Generic Teratogenic Phthalimides Thalidomide, Lenalidomide and Pomalidomide

Thalidomide (α-phthalimidoglutaride) was marketed in the 1950s and early 1960s; it was promoted as a sedative-hypnotic agent with minimal hangover. It was available in some countries as an over-the-counter medicine. Publications reporting profound teratogenic effects with thalidomide brought about major revisions to the monitoring of the safety of medicines. As a consequence of previously unrecognised teratogenic effects, it has been estimated that over 12,000 children were born with a range of defects and disabilities, including severe congenital anomalies. Notably, it has been hypothesised that around 40% of babies with thalidomide-induced malformations born during the 1950s and 1960s died in the neonatal period. The commonest causes of death were atresia of the small bowel, cardiac or renal malformations. Nevertheless, phocomelia (as a typical manifestation of thalidomide´s teratogenic effects) has been reported once again after thalidomide was approved for use in areas where leprosy is endemic. As a result, thalidomide embryopathy remains an important topic in countries such as Brazil. Nowadays thalidomide is approved around the world for the treatment of a wide range of conditions, including leprosy, Crohn's disease, multiple myeloma, and certain malignant solid tumours. Second-generation immunmodulatory drugs including lenalidomide and pomalidomide have received approval for use in the management of various forms of neoplastic disease. Based on clinical experience with thalidomide and its derivatives, learnings have been transferred to further research on a subset of substituted phthalimides each of which has a high risk of causing teratogenic effects. This group of phthalimides is classified within regulatory science as human teratogens. In order to gain approval, a Pregnancy Prevention Programme (PPP), along with a Controlled Distribution System (CDS) is required. The challenges of PPPs in particular for a generic manufacturer have been described, including Raising of awareness, and education; Special aspects of data collection and evaluation; Ethically and socially relevant aspects, and Utilising existing information technology and infrastructure. This paper highlights the risks of unplanned pregnancies, provides information on the regulatory background, and regulatory expectations. Our aim is to provide insights and practical learnings that have impacted operational risk management with the teratogenic phthalimides. Opportunities are presented that may support the implementation of harmonised approaches for PPP and CDS using existing IT-systems across countries and companies.

Comparative analysis of the use and control of thalidomide in Brazil and different countries: is it possible to say there is safety?

INTRODUCTION

One of the biggest drug disasters in history has not prevented thalidomide from being used to treat various clinical conditions. Currently, Brazil has a worrying scenario: high consumption of the drug and, cases of pregnant women using thalidomide, even after adopting restrictive legislation.

AREAS COVERED

This review of the literature and legislation sought to comparatively analyze the monitoring of thalidomide use in Brazil and other countries that use this drug. Finally, we discuss the differences between the countries.

EXPERT OPINION

This analysis allows us to think beyond the safe use of thalidomide, but the safety provided by any type of monitoring system. It seems that out-patients that use unsafe drugs are exposed to some degree of risk. To improve safety, more extensive improvements are needed than monitoring systems related to the use of thalidomide. Its safe use depends on a drastic reduction in the incidence of leprosy and Erythema Nodosum Leprosum in the world; investment in research and development of safe and effective therapeutic alternatives to thalidomide; improvement of health systems and their health surveillance systems, particularly in primary health care; awareness of health professionals and patients for greater responsibility in the use of medicines, especially thalidomide.

Rationale use of Thalidomide in erythema nodosum leprosum - A non-systematic critical analysis of published case reports

INTRODUCTION

Thalidomide is an anti- tumor necrosis factor alpha (TNF-a) drug used mainly in the management of moderate to severe form of Erythema Nodosum Leprosum (ENL). Because of its teratogenic potential it has to be used under proper supervision. Our critical analysis tries to look into the rationale with which it has been used by means of case reports on lepra reaction.

METHODS

We looked for the case reports between December 2005 to June 2019 in databases like Pubmed, Embase and other relevant resources. We used search words like "erythema nodosum leprosum(ENL)", "thalidomide", "case report" in different combinations to get relevant reports that focus on thalidomide usage atleast once at any time point during management. The information extracted were indication of thalidomide use, dose, response, outcome, complication if any, along with all the demographic details and geographical distribution.

RESULTS

We found 41 case reports eligible for analysis.The information was critically evaluated. From the analysis it was found that 7 of the case report mentioned the exact indication, 4 case report showed irrational use of thalidomide in the case of neuritis without use of steroids, 7 showed proper use of Clofazimine prior to thalidomide initiation, 26 case report showed case report of rationale dose range and in 4 case reports clofazimine was used prior to thalidomide along with the rational dose of thalidomide.

CONCLUSIONS

This analysis helps to guide the rationale use of thalidomide focussing on few important points that anyone should keep in mind while managing a case of ENL.

The organization, weaknesses, and challenges of the control of thalidomide in Brazil: A review

The drug thalidomide has resurged in the world market under restrictive conditions for marketing and use. In Brazil, there are still cases of pregnant women using thalidomide even after the implementation of laws that regulate the control of use (Law No. 10.651/2003 and Collegiate Board Resolution No. 11/2011). The objective of this study was to discuss the control of thalidomide use in Brazil, based on a scoping review of the scientific literature, documents, and data from the Ministry of Health. A total of 51 studies and documents related to the following subthemes were selected: (1) organization of access and use of thalidomide in the health system; (2) epidemiological and population characteristics of people affected by leprosy; and (3) occurrence of pregnancy and cases of embryopathy with the use of thalidomide. The results showed that Brazil has no unified information database about thalidomide patients. Furthermore, there is inconsistency in the accreditation of public health centers that dispense this medicine, in a country that has a high consumption of thalidomide in the Unified Health System. A large part of this amount of dispensed medicine is intended for the treatment of erythema nodosum leprosum, mainly in the North, Northeast, and Central-West regions of the country, which are endemic for leprosy. This disease is the only one among the clinical indications of the medicine approved in Brazil that does not have a Clinical Protocol and Therapeutic Guidelines. The control of thalidomide use in Brazil presents historical regulatory failures. These are currently linked to the organization and structure of primary healthcare in the country, as well as to the lack of leadership of the Ministry of Health and National Health Surveillance Agency when it comes to managing the process of control of this use.

Molecular Mechanisms of the Teratogenic Effects of Thalidomide

Thalidomide was sold worldwide as a sedative over 60 years ago, but it was quickly withdrawn from the market due to its teratogenic effects. Thalidomide was later found to have therapeutic effects in several diseases, although the molecular mechanisms remained unclear. The discovery of cereblon (CRBN), the direct target of thalidomide, a decade ago greatly improved our understanding of its mechanism of action. Accumulating evidence has shown that CRBN functions as a substrate of Cullin RING E3 ligase (CRL4^CRBN), whose specificity is controlled by ligands such as thalidomide. For example, lenalidomide and pomalidomide, well-known thalidomide derivatives, degrade the neosubstrates Ikaros and Aiolos, resulting in anti-proliferative effects in multiple myeloma. Recently, novel CRBN-binding drugs have been developed. However, for the safe handling of thalidomide and its derivatives, a greater understanding of the mechanisms of its adverse effects is required. The teratogenic effects of thalidomide occur in multiple tissues in the developing fetus and vary in phenotype, making it difficult to clarify this issue. Recently, several CRBN neosubstrates (e.g., SALL4 (Spalt Like Transcription Factor 4) and p63 (Tumor Protein P63)) have been identified as candidate mediators of thalidomide teratogenicity. In this review, we describe the current understanding of molecular mechanisms of thalidomide, particularly in the context of its teratogenicity.

The role of ESCO2, SALL4 and TBX5 genes in the susceptibility to thalidomide teratogenesis

Thalidomide is widely used for several diseases; however, it causes malformations in embryos exposed during pregnancy. The complete understanding of the mechanisms by which thalidomide affects the embryo development has not yet been obtained. The phenotypic similarity makes TE a phenocopy of syndromes caused by mutations in ESCO2, SALL4 and TBX5 genes. Recently, SALL4 and TBX5 were demonstrated to be thalidomide targets. To understand if these genes act in the TE development, we sequenced them in 27 individuals with TE; we verified how thalidomide affect them in human pluripotent stem cells (hPSCs) through a differential gene expression (DGE) analysis from GSE63935; and we evaluated how these genes are functionally related through an interaction network analysis. We identified 8 variants in ESCO2, 15 in SALL4 and 15 in TBX5. We compared allelic frequencies with data from ExAC, 1000 Genomes and ABraOM databases; eight variants were significantly different (p < 0.05). Eleven variants in SALL4 and TBX5 were previously associated with cardiac diseases or malformations; however, in TE sample there was no association. Variant effect prediction tools showed 97% of the variants with potential to influence in these genes regulation. DGE analysis showed a significant reduction of ESCO2 in hPSCs after thalidomide exposure.

Adverse events in patients with leprosy on treatment with thalidomide

INTRODUCTION

Thalidomide, used to treat erythema nodosum leprosum (ENL), is associated with severe adverse events (AEs) and is highly teratogenic.

METHODS

A cross-sectional study was conducted on thalidomide-treated patients with ENL. AEs and selected variables were investigated through interviews and assessment of medical records. Odds ratios with 95% confidence intervals were estimated via logistic regression.

RESULTS

Peripheral neuropathy symptoms and deep vein thrombosis (DVT) were the most common AEs reported. Although women of reproductive age used contraceptives, <50% of patients reported using condoms. Polypharmacy was associated with all endpoints, except DVT.

CONCLUSIONS

Pharmacovigilance is crucial to prevent harmful thalidomide-associated AEs.

From abortion-inducing medications to Zika Virus Syndrome: 27 years experience of the First Teratogen Information Service in Latin America

In 1990, the first Teratogen Information Service in Brazil (SIAT) was implemented in the Medical Genetics Service at Hospital de Clinicas de Porto Alegre. SIAT is a free-to-use information service both to health professionals and the general population, especially to women who are pregnant or planning pregnancy. The main objective of this paper is to present the activities of SIAT in its initial years (1990-2006), compared to those in the last decade (2007-2017). In addition we review the scientific contribution of SIAT in the field of human teratogenesis. Since 1990, SIAT received 10,533 calls. Use of medications were the main reason for concern, accounting for 74% of all questions, followed by other chemical exposures (occupational, cosmetics, environmental), and maternal infectious diseases. Among its main contributions to scientific knowledge was the collaboration for the identification of two new human teratogens: misoprostol in the 1990s and Zika virus in 2015/16. In conclusion, SIAT is still evolving, as is the Medical Genetics Service that hosts it. Through its 27 years of existence more than 300 undergraduate and graduate students have rotated at SIAT. Presently, SIAT is expanding the research to experimental teratogenesis and to investigation of molecular mechanisms of teratogens.

Teratogens: a public health issue - a Brazilian overview

Congenital anomalies are already the second cause of infant mortality in Brazil, as in many other middle-income countries in Latin America. Birth defects are a result of both genetic and environmental factors, but a multifactorial etiology has been more frequently observed. Here, we address the environmental causes of birth defects - or teratogens - as a public health issue and present their mechanisms of action, categories and their respective maternal-fetal deleterious effects. We also present a survey from 2008 to 2013 of Brazilian cases involving congenital anomalies (annual average of 20,205), fetal deaths (annual average of 1,530), infant hospitalizations (annual average of 82,452), number of deaths of hospitalized infants (annual average of 2,175), and the average cost of hospitalizations (annual cost of $7,758). Moreover, we report on Brazilian cases of teratogenesis due to the recent Zika virus infection, and to the use of misoprostol, thalidomide, alcohol and illicit drugs. Special attention has been given to the Zika virus infection, now proven to be responsible for the microcephaly outbreak in Brazil, with 8,039 cases under investigation (from October 2015 to June 2016). From those cases, 1,616 were confirmed and 324 deaths occurred due to microcephaly complications or alterations on the central nervous system. Congenital anomalies impact life quality and raise costs in specialized care, justifying the classification of teratogens as a public health issue.

The impact of thalidomide use in birth defects in Brazil

Although the thalidomide tragedy occurred more than 50 years ago, the medication is still being used worldwide for different reasons, and several aspects regarding its teratogenicity remain unsolved. Despite the strict regulation implemented, new cases of thalidomide embryopathy (TE) are still being registered in Brazil. Furthermore, the molecular processes that lead to malformations when the embryo is exposed to thalidomide have not yet been fully identified. In this article, we perform a critical analysis of thalidomide's history in Brazil, highlighting aspects of the occurrence of TE over the decades. Finally, we present the main perspectives and challenges for ongoing surveillance and prevention of TE in Brazil. The effective control of dispensing thalidomide, especially in areas where leprosy is endemic, is one of the most important and challenging points. Furthermore, the emergence of thalidomide analogues is fast approaching, and their availability would pose additional concerns. The understanding of the molecular mechanisms and targets of thalidomide in both experimental and human models is essential for generating new insights into teratogenic mechanisms, so that safer thalidomide analogues can be developed.

Zika Fetal Neuropathogenesis: Etiology of a Viral Syndrome

The ongoing Zika virus epidemic in the Americas and the observed association with both fetal abnormalities (primary microcephaly) and adult autoimmune pathology (Guillain-Barré syndrome) has brought attention to this neglected pathogen. While initial case studies generated significant interest in the Zika virus outbreak, larger prospective epidemiology and basic virology studies examining the mechanisms of Zika viral infection and associated pathophysiology are only now starting to be published. In this review, we analyze Zika fetal neuropathogenesis from a comparative pathology perspective, using the historic metaphor of "TORCH" viral pathogenesis to provide context. By drawing parallels to other viral infections of the fetus, we identify common themes and mechanisms that may illuminate the observed pathology. The existing data on the susceptibility of various cells to both Zika and other flavivirus infections are summarized. Finally, we highlight relevant aspects of the known molecular mechanisms of flavivirus replication.